view mercurial/help/filesets.txt @ 17202:1ae119269ddc

hgweb: side-by-side comparison functionality

Adds new web command to the core, ``comparison``, which enables colorful
side-by-side change display, which for some might be much easier to work with
than the standard line diff output. The idea how to implement comes from the
SonicHq extension.
The web interface gets a new link to call the comparison functionality. It lets
users configure the amount of context lines around change blocks, or to show
full files - check help (also in this changeset) for details and defaults. The
setting in hgrc can be overridden by adding ``context=<value>`` to the request
query string. The comparison creates addressable lines, so as to enable sharing
links to specific lines, just as standard diff does.
Incorporates updates to all web related styles.

Known limitations:
* the column diff is done against the first parent, just as the standard diff
* this change allows examining diffs for single files only (as I am not sure if
  examining the whole changeset in this way would be helpful)
* syntax highlighting of the output changes is not performed (enabling the
  highlight extension has no influence on it)

Mercurial supports a functional language for selecting a set of
files. 

Like other file patterns, this pattern type is indicated by a prefix,
'set:'. The language supports a number of predicates which are joined
by infix operators. Parenthesis can be used for grouping.

Identifiers such as filenames or patterns must be quoted with single
or double quotes if they contain characters outside of
``[.*{}[]?/\_a-zA-Z0-9\x80-\xff]`` or if they match one of the
predefined predicates. This generally applies to file patterns other
than globs and arguments for predicates.

Special characters can be used in quoted identifiers by escaping them,
e.g., ``\n`` is interpreted as a newline. To prevent them from being
interpreted, strings can be prefixed with ``r``, e.g. ``r'...'``.

There is a single prefix operator:

``not x``
  Files not in x. Short form is ``! x``.

These are the supported infix operators:

``x and y``
  The intersection of files in x and y. Short form is ``x & y``.

``x or y``
  The union of files in x and y. There are two alternative short
  forms: ``x | y`` and ``x + y``.

``x - y``
  Files in x but not in y.

The following predicates are supported:

.. predicatesmarker

Some sample queries:

- Show status of files that appear to be binary in the working directory::

    hg status -A "set:binary()"

- Forget files that are in .hgignore but are already tracked::

    hg forget "set:hgignore() and not ignored()"

- Find text files that contain a string::

    hg locate "set:grep(magic) and not binary()"

- Find C files in a non-standard encoding::

    hg locate "set:**.c and not encoding('UTF-8')"

- Revert copies of large binary files::

    hg revert "set:copied() and binary() and size('>1M')"

- Remove files listed in foo.lst that contain the letter a or b::

    hg remove "set: 'listfile:foo.lst' and (**a* or **b*)"

See also :hg:`help patterns`.